Parameter Estimation with Reluctant Quantum Walks: a Maximum Likelihood
approach
- URL: http://arxiv.org/abs/2202.11846v2
- Date: Tue, 30 May 2023 00:54:07 GMT
- Title: Parameter Estimation with Reluctant Quantum Walks: a Maximum Likelihood
approach
- Authors: Demosthenes Ellinas, Peter D. Jarvis and Matthew Pearce
- Abstract summary: A coin action is presented, with the real parameter $theta$ to be estimated.
For $k$ large, we show that the likelihood is sharply peaked at a displacement determined by the ratio $d/k$.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The parametric maximum likelihood estimation problem is addressed in the
context of quantum walk theory for quantum walks on the lattice of integers. A
coin action is presented, with the real parameter $\theta$ to be estimated
identified with the angular argument of an orthogonal reshuffling matrix. We
provide analytic results for the probability distribution for a quantum walker
to be displaced by $d$ units from its initial position after $k$ steps. For $k$
large, we show that the likelihood is sharply peaked at a displacement
determined by the ratio $d/k$, which is correlated with the reshuffling
parameter $\theta$. We suggest that this `reluctant walker' behaviour provides
the framework for maximum likelihood estimation analysis, allowing for robust
parameter estimation of $\theta$ via return probabilities of closed evolution
loops and quantum measurements of the position of quantum walker
with`reluctance index' $r=d/k$.
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